Panels with an optional through-vision facility

ABSTRACT

A panel with an optional through-vision facility comprising three sheets with transparent areas, the sheets being arranged as a superposed pair of outer sheets secured in a rigid frame with a third or centre sheet slidably sandwiched between the two said outer sheets, the centre sheet and one or both said outer sheets being marked with strips of at least reduced transparency whereby sliding movement of the centre sheet with respect to the outer sheets causes a variation in overall through-vision of the panel, the rigid frame of the panel being formed as a rectangle with a generally U-shaped channel cross-section and the sides of the rectangle having members disposed in the channel on the base of the U to space the outer sheets apart, cam means being operable on the centre sheet to move it slidably with respect to the two outer sheets.

Steele PANELS WITH AN OPTIONAL THROUGH-VISION FACILITY 3,814,506 June 4,1974

[75] Inventor: Astor Andrew Steele, London,

England [57] ABSTRACT [73] Assignee: Steele's (Contractors) Limited, A panel with an optional through-vision facility com- London, England prising three sheets with transparent areas. the sheets being arranged as a superposed pair of outer sheets [22] 1973 secured in a rigid frame with a third or centre sheet [2l] Appl. No.: 322,103 slidably sandwiched between the two said outer sheets. the centre sheet and one or both said outer sheets being marked with strips of at least reduced 7 7 2% 350/272 g 7gg transparency whereby sliding movement of the centre i 260 sheet with respect to the outer sheets causes a varia- 0 are 6/ tion in overall through-vision of the panel, the rigid frame of the panel being formed as a rectangle with a generally U-shaped channel cross-section and the [56] References C'ted sides of the rectangle having members disposed in the UNITED STATES PATENTS channel on the base of the U to space the outer sheets 1.816.112 7/1931 Dicsch 350/266 apart, cam means being operable on the centre sheet 2.1861113 1/1940 Ccnteno 350/272 10 move it slidably with respect to the two outer 2.255.933 9/l94l Land 350/263 Sheets 3.665.9l5 5/1972 Katona ct al. 350/272 13 Claims, 14 Drawing Figures 1E 1 0 Ll fi lii ,4 L ,,7 ul [1 7 1 7 1 I 1 1 1 r] h i I 11 1I I l I 1 1 L- V 1 1 I EH h 1 111 111 l l 1 I l 1 I 1 i 1 111 II 1 i i i 1 i I I] 1,: 1 1 a 1 I 1 1 1 1 l 1 1% .1 1' j l 1 11 1 l I PANELS WITH AN OPTIONAL THROUGH-VISION FACILITY The present invention relates to panels with an optional through-vision facility of a general type which is of particular use for fitting in hospital doors or windows but which may also for instance be used in the doors or windows of nursing homes, banks, offices, laboratories, post offices, nurseries and private residences, the purpose of such panels being to provide an option between through-vision and vision cut-off.

Previous vision panels (as such panels will be referred to hereinafter for convenience) have been proposed which generally comprise a pair of glass sheets arranged in spaced apart parallel relationship with a third sheet movable parallel thereto in the space therebetween, such movement being under the control of'a cam operable by a knob. The two outer sheets are marked with mutually overlying opaque strips so as to provide through-vision between the said strips and the third sheet is similarly marked but, being moveable under the control of the cam, may adopt a position in which its opaque strips lie in correspondence with the outer sheet opaque strips, or a position in which its opaque strips lie between the outer sheet opaque strips, or any position therebetween. As will be evident such movement of the inner sheet controls the degree to which there is through-vision or cut-off by the panel as a whole.

Various disadvantages have been found to exist with such previously proposed panels and the main such disadvantage stems from the fact that to date it has been generalto edge the panel with tape of one form or another. As a result, when the panel is secured to a window frame e.g., in a door, between a fixed bead and a removable bead it is only too easy for the workman making such fixing to compress the panel between the beads (no resistance to compression being offered by the tape) and detract from smooth and reliable operation, i.e., smooth movement of the inner sheet between the two outer sheets.

It is an object of the present invention to provide a vision panel which overcomes or at least minimises the above mentioned disadvantage and provides for fixing by even relatively unskilled workmen.

According to the present invention there is provided a panel with an optional through-vision facility comprising three sheets with transparent areas, the sheets being arranged as a superposed pair of outer sheets secured in a rigid frame with a third or centre sheet slidably sandwiched between the two said outer sheets, the centre sheet and one or both said outer sheets being marked with strips of at least reduced transparency whereby sliding movement of the centre sheet with respect to the outer sheets causes a variation in overall through-vision of the panel, the rigid frame of the panel being formed as a rectangle with a generally U-shaped channel cross-section and the sides of the rectangle having members disposed in the channel on the base of the U to space the outer sheets apart, cam means being operable on the centre sheet to move it slidably with respect to the two outer sheets.

Difficulties have also been experienced with previously proposed panels which difficulties stem from the fact that the central sheet is movable under the control of a cam which is moved by a knob. Such difficulties result from the fact that the knob is frequently of necessity located too close to the aforementioned beading for the hand of an operator to obtain good purchase thereon.

In accordance with a preferred embodiment of the invention therefore, the cam means of the panel is operable by a rod which extends through the outer sheets and carries instead of a knob a lever at each end. Conveniently the levers are secured to the said rod by screw clamping means covered by a flush-fitting screw cap.

This latter arrangement is of course an advantage in hospitals and the like where it is essential to reduce the number of recesses in which germs and the like may collect. Also, a lever is of course more readily wiped and cleaned that a knob and clearly provides for better mechanical purchase.

In order that the invention may be more readily understood reference will now be made to the accompanying drawings which are given by way of example and in which:

FIG. I is a simplified plan view of a panel according to the present invention,

FIG. 2 is a side view of the panel FIG. 1,

FIGS. 3, 4a and 4b are respectively side, top and end views of a side rail of a frame for the panel of the invention,

FIGS. 5, 5a and 5b are respectively side, top and end views of a top rail of a frame for the panel of the invention,

FIGS. 6, 6a and 6b are respectively side, top and end views of a bottom rail of a frame for a panel according to the invention,

FIG. 7 is a general view of a control lever and cam for a panel according to the invention,

FIG. 8 is an exploded view of an arrangement for mounting two such control levers, and

FIG. 9 shows a nylon bush for use in association with the arrangement shown in FIGS. 7 and 8.

The panel shown in FIGS. 1 and 2 comprises a pre dominantly metal frame 1, which is generally rectangular in form and superficially resembles a picture frame. The frame 1 is formed from two side rails la, a top rail lb and a bottom rail Ic. The rails Ia, lb and 1c are as shown in detail respectively in FIGS. 3, 4a and 4b; 5, 5a and 5b; and 6, 6a and 6b.

As will be evident, the four rails are similar in that they each terminate with a bevelled end 2, some being provided with an end flange member 3, which is perforated at 4, and others with a perforation 30. The perforatibns may be tapped or may be untapped suitable for receiving a selftapping screw. In either case there is easy assembly of the four rails to form the rectangular frame 1. Further details will not be given of the corner construction as it may be modified in any suitable or known manner at will and does not constitute an essential part of the present invention. For instance the rail ends need not be bevelled and may interengage in any other desired and suitable manner.

As will be seen from the aforementioned figures, the four rails are each of channel form in cross-section, and the two side rails In each comprise nylon runners 5, which are mounted by fixing rods 6 secured to the base of the rail channel. The top rail lb has no side nylon runners but is instead provided with a pair of curved phosphor-bronze pressure springs 7 each secured at one end to the base of the channel of the said rail. The bottom rail is provided with a central nylon cam member 8 which functions as a cam stop for a cam to be later described and is also mounted by a said rod 6. Also mounted by further rods 6 are a pair of nylon bottom stops 9, one bottom stop 9 being disposed on either side of the cam stop 8. As illustrated, the nylon bottom stops 9 stand higher than the cam stop 8.

The fixing rods and springs are conveniently, but not essentially, spot welded to their associated rails. other means of fixing being envisaged as desired.

As will now be evident, when the four rails are joined together to form the rectangular frame 1, there is defined a frame which will securely receive two sheetsof glass 10 and 11, one said sheet being disposed on each side of the side runners and stops 8 and 9. In between the sheets and 11 there is provided a further glass sheet 12 of which the side edges rest on the outer surfaces of the side runners 5, and which is urged in a downward direction by the pressure springs 7 acting on its top edge. This downwardly urged sheet 12 rests with its bottom edge on the stops 9 or on the cam shown in FIG. 7 and generally referenced 13. The cam 13 is operable by lever controls 14 in a manner which will later be detailed and the cam 13 at its lower surface abuts the cam stop 8. The sheet 12 engages the nylon bottom stops 9 in a rest position i.e. with the cam 13 in such a position as to be out of contact with the sheet 12, and with the latter resting on the bottom stops 9. lf however the cam 13 is turned by a lever 14, the said cam will cause the sheet 12 to move upwards in its sandwich relationship with the outer sheets 10 and 11. The extent to which the sheet 12 may move upwards is limited by the springs 7 and the confines of the upper rail channel lb and the said sheet 12 is kept firmly in engagement with the cam by virtue of the resilient characteristics of the springs 7.

ln accordance with known techniques at least one of the sheets 10, 11 is sand blasted in strip areas to destry or reduce the transparency of the said sheet in the strips. The sheet I2 is similarly treated and the dimensioning and mutual arrangement of the strips on the sheets is such that movement of the sheet 12 with respect to the sheets 10 and 11 will cause a shuttering effeet. When the strips of the two sheets overlie each other there is maximum through vision via the panel and when the strips are out of alignment there is a full or partial cut-off of through vision. The sheets need not of course be of glass (other materials such as plastics may be used) and as an alternative to sand blasting there is instanced integral colouring, painting or masking by any suitable means.

As will by now be evident, movement of a control lever 14 will move the cam 13 to control through vision.

As illustrated in FIGS. 7, 8 and 9 a matching pair of brass control levers 14 is provided, each key splined to a brass shaft 15, which shaft has a central square portion 16, which is a non-rotatable fit within the cam 13. A nylon bush 17 is mounted in the glass which is suitably perforated. Control of the cam 13 is by one of the two said control levers 14, disposed one lever on each side of the panel of the invention. At each end of shaft there is screw fitted a flush cap l8.

Various modifications of the invention are, of course, possible over and above those previously indicated and particularly modifications are possible with respect-to the arrangement shown in FIGS. 7. 8 and 9. For instance the levers 14 may be replaced by knobs and any suitable arrangement for securing the knobs to the cam may be adopted. Also the shape of the cam may be modified as required. The runners, springs and stops may be of any suitable material.

I claim:

1. A panel with an optional through-vision facility comprising three sheets with transparent areas. the sheets being arranged as a superposed pair of outer sheets secured in a rigid frame with a third centre sheet slidably sandwiched between the two said outer sheets, the centre sheet and at least one of said outer sheets being marked with strips of at least reduced transparency whereby sliding movement of the centre sheet with respect to the outer sheets causes a variation in overall through-vision of the panel, the rigid frame of the panel being formed as a rectangle with a generally U-shaped channel cross-section and the sides of the rectangle having members disposed in the channel on the base of the U to space the outer sheets apart, cam means engageable with said centre sheet and operable on the centre sheet to move it slidably with respect to the two outer sheets, means comprising runners disposed on either side of said centre sheet, and bottom stop means for engaging the centre sheet in its rest position.

2. A panel according to claim 1 wherein the said centre sheet runs over the outer free surfaces of the said side members.

3. A panel according to claim 1 wherein the frame is formed from four rails, being two side rails, a top rail and a bottom rail.

4. A panel according to claim 3 wherein the four rails are bevelled at their ends and provided with means for interengagement.

5. A panel according to claim 4 wherein the means for interengagement comprise end flange members and perforations for receiving screws.

6. A panel according to claim 1 wherein the side members are formed as nylon blocks mounted by fixing rods spot-welded in the channel on the U base, the axis of the fixing rods being generally parallel to the longitudinal axis of the said channels.

7. A panel according to claim 1 comprising a pair of pressure springs as curved phosphor-bronze springs, the said pressure springs being so located as to urge the movable centre sheet into engagement with the said cam means.

8. A panel according to claim 1 wherein said stop means comprises a pair of bottom stops mounted one each side of the said cam stop, which bottom stops limit downward movement of the said centre sheet.

9. A panel according to claim 8 wherein the said cam and bottom stops are formed of nylon and are mounted on fixing rods spot-welded in the channel of the U base, the axis of the fixing rods being generally parallel to the longitudinal axis of the said channels.

10. A panel according to claim 1 wherein the said cam means is mounted on a rod extending through the outer sheets, the said rod carrying a control lever at each end whereby the centre sheet may be controlled from either side of the panel.

3,814,506 6 11. A panel according to claim 10 wherein the levers 13. A panel according to claim 1 wherein the three are secured to the.rod by screw clampmg means sheets are of glass and the centre and one outer sheet ered by a flush-fitting screw cap.

12. A panel according to claim 1 wherein the said are Sand blasted in strips frame is formed predominantly from metal. 5 

1. A panel with an optional through-vision facility comprising three sheets with transparent areas, the sheets being arranged as a superposed pair of outer sheets secured in a rigid frame with a third centre sheet slidably sandwiched between the two said outer sheets, the centre sheet and at least one of said outer sheets being marked with strips of at least reduced transparency whereby sliding movement of the centre sheet with respect to the outer sheets causes a variation in overall through-vision of the panel, the rigid frame of the panel being formed as a rectangle with a generally U-shaped channel cross-section and the sides of the rectangle having members disposed in the channel on the base of the U to space the outer sheets apart, cam means engageable with said centre sheet and operable on the centre sheet to move it slidably with respect to the two outer sheets, means comprising runners disposed on either side of said centre sheet, and bottom stop means for engaging the centre sheet in its rest position.
 2. A panel according to claim 1 wherein the said centre sheet runs over the outer free surfaces of the said side members.
 3. A panel according to claim 1 wherein the frame is formed from four rails, being two side rails, a top rail and a bottom rail.
 4. A panel according to claim 3 wherein the four rails are bevelled at their ends and provided with means for interengagement.
 5. A panel according to claim 4 wherein the means for interengagement comprise end flange members and perforations for receiving screws.
 6. A panel according to claim 1 wherein the side members are formed as nylon blocks mounted by fixing rods spot-welded in the channel on the U base, the axis of the fixing rods being generally parallel to the longitudinal axis of the said channels.
 7. A panel according to claim 1 comprising a pair of pressure springs as curved phosphor-bronze springs, the said pressure springs being so located as to urge the movable centre sheet into engagement with the said cam means.
 8. A panel according to claim 1 wherein said stop means comprises a pair of bottom stops mounted one each side of the said cam stop, which bottom stops limit downward movement of the said centre sheet.
 9. A panel according to claim 8 wherein the said cam and bottom stops are formed of nylon and are mounted on fixing rods spot-welded in the channel of the U base, the axis of the fixing rods being generally parallel to the longitudinal axis of the said channels.
 10. A panel according to claim 1 wherein the said cam means is mounted on a rod extending through the outer sheets, the said rod carrying a control lever at each end whereby the centre sheet may be controlled from either side of the panel.
 11. A panel according to claim 10 wherein the levers are secured to the rod by screw clamping means covered by a flush-fitting screw cap.
 12. A panel according to claim 1 wherein the said frame is formed predominantly from metal.
 13. A panel according to claim 1 wherein the three sheets are of glass and the centre and one outer sheet are sand blasted in strips. 